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arXiv · 1108.4571

Graphene Nanogap for Gate Tunable Quantum Coherent Single Molecule Electronics

A. Bergvall·K. Berland·P. Hyldgaard·S. Kubatkin·T. Lofwander
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Abstract

We present atomistic calculations of quantum coherent electron transport through fulleropyrrolidine terminated molecules bridging a graphene nanogap. We predict that three difficult problems in molecular electronics with single molecules may be solved by utilizing graphene contacts: (1) a back gate modulating the Fermi level in the graphene leads facilitate control of the device conductance in a transistor effect with high on/off current ratio; (2) the size mismatch between leads and molecule is avoided, in contrast to the traditional metal contacts; (3) as a consequence, distinct features in charge flow patterns throughout the device are directly detectable by scanning techniques. We show that moderate graphene edge disorder is unimportant for the transistor function.

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A. Bergvall, K. Berland, P. Hyldgaard, S. Kubatkin, T. Lofwander. 2011-08-23. Graphene Nanogap for Gate Tunable Quantum Coherent Single Molecule Electronics. https://doi.org/10.1103/physrevb.84.155451

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